In the present work, rapidly solidified Al-10Ni-XSc (X = 0, 1 and 2) alloys were fabricated by melt spinning under Ar atmosphere. The Effects of Sc on the microstructural and thermal properties and microhardness values were investigated by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and a Vickers microhardness tester. Experimental results revealed that the addition of 2 wt. % Sc to melt-spun Al-10Ni alloys changed their brittle nature and hindered formation of cracks. The addition of Sc to melt-spun Al-10Ni alloys also changed the morphology of Al3Ni intermetallics from an acicular/needle – like to a rounded particle-like structure and led to reduction in their size. Formation of the metastable Al9Ni2 phase was observed due to the higher constitutional undercooling caused by Sc addition. A considerable improvement in microhardness value (from 95. 9 to 230. 1 HV) was observed with the addition of Sc.
The aim of this work was to investigate the possibility of obtaining an amorphous/crystalline composite starting from Ni-Si- B-based powder grade 1559-40 and silver powder. The alloy was produced using arc melting of 95% wt. Ni-Si-B-based powder (1559-40) and 5% wt. Ag powder. Ingot was re-melted on a copper plate and observed while cooling using a mid-wave infra-red camera. The alloy was then melt-spun in a helium atmosphere. The microstructure of the ingot as well as the melt-spun ribbon was studied using light microscopy and scanning electron microscopy with energy dispersive spectrometry. Phase identification was performed by means of X-ray diffraction. The observations confirmed an amorphous/crystalline microstructure of the ribbon where the predominant constituent of the microstructure was an amorphous phase enriched with Ni, Si, and B, while the minor constituent was an Ag-rich crystalline phase distributed in a film along the melt-spinning direction.